There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
The osteoblast is the bone-forming cell. The molecular basis of osteoblast-specific
gene expression and differentiation is unknown. We previously identified an osteoblast-specific
cis-acting element, termed OSE2, in the Osteocalcin promoter. We have now cloned the
cDNA encoding Osf2/Cbfa1, the protein that binds to OSE2. Osf2/Cbfa1 expression is
initiated in the mesenchymal condensations of the developing skeleton, is strictly
restricted to cells of the osteoblast lineage thereafter, and is regulated by BMP7
and vitamin D3. Osf2/Cbfa1 binds to and regulates the expression of multiple genes
expressed in osteoblasts. Finally, forced expression of Osf2/Cbfa1 in nonosteoblastic
cells induces the expression of the principal osteoblast-specific genes. This study
identifies Osf2/Cbfa1 as an osteoblast-specific transcription factor and as a regulator
of osteoblast differentiation.